Mesothelioma is a destructive disease that can change the entire trajectory of people’s lives. Since it was first identified in the early 20th century, there has been much research into mesothelioma. In recent years, an increase in clinical trials and further studies has helped identify new treatment options for the disease. But, is there a cure for mesothelioma?
Unfortunately, the answer to that question is still no. While scientists, researchers, and medical professionals are hard at work trying to find a mesothelioma cure, they are not yet there. Remission is possible, but the fast-acting nature of the cancer makes that rare.
Still, new treatment methods and procedures have helped extend lifespans for numerous mesothelioma patients throughout the world. The standard multimodal treatment therapy for mesothelioma has typically included:
- Radiation therapy
Many new treatments are now being thrown into the mix as well. With any luck, in the near future, patients who suffer from mesothelioma will be able to do much more than just hope that current treatment options will work.
History of Mesothelioma Cure Research
Mesothelioma didn’t receive its name until about 1920. Scientists at the time had known about the adverse effects caused by asbestos exposure and inhalation (the primary cause of mesothelioma), but they didn’t devise a specific name for the ailment until 1920. Mesothelioma was just one of many different complications caused by exposure to asbestos. This fact was confirmed by studies in the 1960s.
In the 1940s, the primary treatment method for pleural mesothelioma (occurring in the lung lining or pleura) was the removal of an entire diseased lung and the pleura surrounding it. These surgeries were often rudimentary by today’s standards and proved to cause many more complications than patients experience now.
Surgical techniques advanced over the following few decades and many procedures became less invasive. New surgical procedures allow for lungs to be saved rather than excised outright. Surgical equipment also improved, allowing surgeons to operate with more precision.
In the early 2000s, chemotherapy and radiation therapy became more commonplace and also helped improve life expectancies and survival rates of mesothelioma patients across the board. In 2004, the U.S. Food and Drug Administration (FDA) approved pemetrexed (brand name, Alimta) for use as a chemotherapy treatment for mesothelioma when paired with cisplatin.
It is so far the only FDA-approved chemotherapy treatment combination for mesothelioma (although many other chemotherapy drugs are also offered to patients off-label).
Finding a Mesothelioma Cure in Clinical Trials
Clinical trials are research tools that allow scientists and researchers to monitor the effect of specific treatments on patients with mesothelioma. They are the best option for identifying emerging and effective treatments.
In fact, the FDA approved pemetrexed for mesothelioma based on positive results in a variety of clinical trials. So, it stands to reason that if a cure for mesothelioma is found, it will be through clinical trials.
In general, clinical trials have four stages:
If a research study is actively recruiting, then patients can check to see if they are eligible for possible enrollment. Clinical trials that are active and not recruiting are generally considered closed to new recruits because research is underway. Completed clinical trials are at the stage where researchers are studying data to make their conclusions.
Clinical trials also occur in phases. Most new drugs and procedures go through four phases of clinical trials in order to be considered for approval by the FDA. Phase I trials are usually relatively small, with only a few dozen participants. The goal of a Phase I trial is to determine if the treatment is safe for use in humans, which is why the number of participants is so limited.
Phase II clinical trials usually involve a few hundred patients. The goal of this phase is to identify how effective the therapy is at treating a specific disease or assemblage of diseases. If a treatment option makes it to Phase III trials, then a certain level of effectiveness has been achieved and confirmed.
Phase III trials seek to compare the new treatment with an already established one. For instance, a new chemotherapy drug for mesothelioma would likely undergo comparison testing with pemetrexed in a Phase III trial. A few thousand participants may be a part of a Phase III trial.
If Phase III trials prove to be successful, the FDA may grant approval for the treatment. Phase IV trials are usually conducted after a treatment option has been made available to the public. These trials are used to further identify any potentially harmful side effects and ensure efficacy and proper dosage.
Most clinical trials have precise eligibility requirements that patients must meet in order to qualify. For the most part, these requirements are based on one or more of the following:
- Age of the patient
- Overall health
- Type of mesothelioma
- Stage (or progression) of the disease
- Whether or not the patient has received other cancer treatments
- Whether the mesothelioma is an original occurrence or a recurrent one
Different trials look for different criteria, so if a patient is denied entry to one, he or she may be accepted into another.
It should also be noted that any clinical trial comes with inherent risks (particularly Phase I trials). These treatments have not been approved for use by the FDA (except in some Phase IV trials), and they can be considered experimental in nature. In some cases, the risks and side effects may be unclear. Of course, any new experimental treatment could turn out to be a cure for mesothelioma or at least an effective treatment for a great number of patients.
Treatments will affect each person differently, so researchers search for the data that shows up most frequently during their analysis. In other words, if a treatment is effective for 80% of the test subjects, that’s great news for those patients and the researchers. For the 20% for whom the treatment was ineffective, it can beheartbreaking.
Emerging Mesothelioma Research
What exactly is researched during mesothelioma clinical trials? For the most part, researchers are testing the efficacy of chemotherapy drugs. But more recently, newly emerging treatments are also being made available to patients via clinical trials.
Some of those treatments include:
- Immunotherapy – medications that cause an immune response in the body that attacks cancerous cells
- Gene therapy – the act of replacing unhealthy or faulty genes with normal ones
- Cryotherapy – using very cold temperatures to kill cancer cells
- Hyperthermic therapy — using very hot temperatures to kill cancer cells
- Photodynamic therapy – using a beam of light to produce cellular changes in photosensitizing agents in the body that can attack cancer cells
- Epigenetic therapy – changing DNA signals from the epigenome to allow for more healthy internal reactions
- Virotherapy – injecting cancer-killing viruses into the body
One of the most promising new mesothelioma treatment options is immunotherapy. Drugs in that class have already been approved for other forms of cancer. Immunotherapy drugs like bevacizumab (Avastin) have also been used to treat mesothelioma when combined with pemetrexed and cisplatin. Pembrolizumab (Keytruda) is currently undergoing Phase II trials for treating mesothelioma.
The goal of all of these medications is essentially to convince the body to attack the cancer with its own immune cells. In many cases, the immune response to the onset of cancer isn’t one of attack because the cancer cells have disguised themselves as healthy cells. Immunotherapy helps spur an appropriate immune response.
Gene therapy is another promising field of study for treating mesothelioma and potentially finding a cure. Many diseases proliferate in the body because of faulty cell genetics. Healthy cells contain naturally tumor-suppressing proteins that help mitigate the growth and spread of cancerous disease. In some people, those proteins have mutated and no longer work properly.
The goal of gene therapy is to eliminate unhealthy or faulty genes and replace them with genes that work properly. Other methods work to genetically reprogram genes in cancer cells so that they release an enzyme that effectively destroys themselves.
Other treatments have only been used as adjuvant therapies, which means that they are applied after surgery in order to eliminate any remaining cancer cells. But even adjuvant therapies can chelp improve life expectancy for many patients and may play key roles in an eventual cure for mesothelioma.
Obstacles to Finding a Mesothelioma Cure
Most mesothelioma research is limited by low number of patients who are viable candidates for aggressive, multimodal treatment approaches. Unfortunately, the disease is most often diagnosed in its later stages, making it far from ideal for study.
In general, an ideal patient has stage 1 or stage 2 mesothelioma, which means that the cancer hasn’t yet spread (or metastasized) toother parts of the body. These patients will benefit the most from aggressive treatments, and they also have the longest life expectancy after diagnosis, even without treatment, making them ideal research participants.
Mesothelioma is typically diagnosed very late in its development for three reasons. The first is the disease’s extremely long latency period. Exposure to asbestos fibers causes mesothelioma, but it can take up to 50 years for symptoms of the disease to start presenting themselves. Unless they worked in a job where asbestos-containing products were frequently used, many people cannot remember if they encountered any asbestos exposure in their lifetimes, especially if it happened fifty years ago.
The second reason that mesothelioma is diagnosed so late is that its symptoms are usually mild and non-specific in stages 1 and 2. Most patients with pleural mesothelioma (occurring in the lining of the lungs) may experience a slight cough and occasional chest pain or difficulty breathing, which might easily be attributed to having smoked or advancing age.
With peritoneal mesothelioma (affecting the lining of the abdominal cavity), early symptoms usually are mistaken for an upset stomach. Symptoms only become noticeable when the disease spreads to other internal organs.
The third reason for a late mesothelioma diagnosis is the relative rarity of the disease . Even when doctors and patients begin to suspect that something major is wrong, mesothelioma is usually the last thing considered. There are much more common types of cancer that exhibit symptoms similar to mesothelioma.
The only way to get an accurate mesothelioma diagnosis is with a tissue biopsy. Even then, some mesothelioma tissue resembles that of non-small-cell lung cancer.
Despite so many challenges, mesothelioma research continues. Patients can remain hopeful that one day research will yield a cure. To people with the disease and those who love them, it may seem like the search for new treatment options is progressing too slowly, but it is best to remember that it is only a matter of time before the right therapy proves to be extremely valuable for all mesothelioma patients.